Model 2401-P

Compact contamination meter

A pocket-size instrument with an integrated pancake GM detector for alpha, beta and gamma checks.

Detector type: Integrated pancake GM1
Count-rate range: 0–660 kcpm2
Weight including battery: 0.4 kg1

Download product sheet (PDF)All values with references – for tender documents

Specifications checked against the manufacturer’s documents on 2026-10-16

Manufacturer’s product page (opens in a new tab)

Overview

Nuclear power & nuclear technology Emergency services & first response Environmental monitoring & radiation protection Industry & quality control

Key features

Portable format for quick surveys.

Specifications

The number after each value refers to the source listed below. Values are as published by the manufacturer; the exact configuration is always confirmed in our quotation.

Detector

Detector type	Integrated pancake GM1
Radiation	Alpha, beta, gamma1
Active detector area	15.51 cm²2

Measuring range

Exposure-rate range	0–200 mR/hr2
Count-rate range	0–660 kcpm2
Response time, typical (10–90%)	11 s1
Energy response	Energy dependent2

Power & battery

Power supply	9 V battery1
Battery life, typical	250 h (alkaline battery, at normal background levels)1

Mechanical

Dimensions (H × W × L)	4.6 × 8.4 × 13.5 cm1

Environment & ratings

Operating temperature	−20 to +50 °C (−4 to 122 °F); may be certified for operation from −40 to +65 °C (−40 to 150 °F)3

Ordering & accessories

Weight including battery	0.4 kg1

General

Alarm	No1

The data comes from the manufacturer’s published documents. Manufacturers may change specifications; the current configuration and performance are confirmed in the quotation.

Documents

PDFModel 2401-P Pocket-Size Survey Meter with Pancake GM (data sheet)Datasheet · Ludlum

Sources

The number after each value refers to the source listed below. Values are as published by the manufacturer; the exact configuration is always confirmed in our quotation.

1
Model 2401-P Pocket-Size Survey Meter with Pancake GM (data sheet)
Publisher: Ludlum MeasurementsDatasheet p. 1, Features and Specifications (DETECTOR); p. 1, Specifications; p. 1, Specifications (BATTERY LIFE) Checked 2026-10-16
2
Model 2401-P Pocket-Size Survey Meter with Pancake GM
Publisher: Ludlum MeasurementsProduct page Specifications tab (Window); Specifications tab (Range); Product page – Specifications Checked 2026-10-16
3
Ludlum Models 2401-EC, 2401-EW, 2401-EC2 and 2401-P manual
Publisher: Ludlum MeasurementsManual Manual p. 15 (p. 5-1), section 5, Environmental Conditions for Normal Use Checked 2026-10-16